1. Field of the Invention
The present invention relates to solenoid actuators. More specifically, the present invention is directed to an input power voltage adaptability for a power management circuit for direct current solenoid valves.
2. Description of the Prior Art
Direct current (DC) operated solenoid valves have been operated from various input voltages, e.g., 12 volts DC to 240 volts AC (alternating current). In order to adapt the solenoid valve to such input voltages, a different solenoid coil is used. This has led to a proliferation of coils required for the same valve body. Further, the ratings of the valves are different for DC and AC operation, e.g., DC operation usually had a lower pressure rating for the same size valve orifice. That situation was obviously uneconomical in terms of valve manufacturing, valve cost and inventory maintenance. Accordingly, it would be desirable to provide a solenoid valve operating circuit having a capability of accommodating a range of AC and DC input power voltage, identified herein as autoranging. Such an autoranging capability would enable a single coil to be used for a valve family which would operate over the aforesaid range of AC and DC input power voltages while automatically maintaining a power management operation for the solenoid coil. This would provide valve ratings which would be the same for AC and DC. Further, such a feature would effect a product cost reduction as a result of providing a larger volume base for manufacturing as well as reducing inventories for manufacturing and distribution while concurrently minimizing parts, machining operations and testing.